The Applicants have already described modular structure installations having a plurality of work stations for assembling and/or machining parts. These installations are described in French patent application No. 80 21976 filed Oct. 14, 1980 and published under the French Pat. No. 2 491 897, in French certificate of addition application No. 81 07088 filed Apr. 8, 1981, and in U.S. Pat. No. 4,519,491 filed Oct. 14, 1981.
These modular and flexible installations for assembling and/or machining are particularly advantageous for short manufacturing runs. In particular, the user may be any moment alter the structure of the installation to optimize its performance as a function of changing needs.
The modular installations described in the above-mentioned patent applications include a conveyor circuit for moving part-carrying pallets. The conveyor circuit serves a succession of work stations for manual and/or automatic assembly and/or machining. The work stations may be associated with the circuit in series and/or in parallel. The Applicants have already described means for providing each pallet with modifiably encoded data.
Each work station then includes means located upstream from the place where the work proper is performed for reading said encoded data, and/or means located downstream therefrom for writing new data (eg. a destination code) on a pallet carrying a part which has been worked on in a manner that was determined by the code initially read from the pallet.
Such encoding makes it possible for data processing means to control the routing of the pallets throughout an installation. However, serious practical difficulties are encountered. Firstly, there is a considerable volume of data to be processed. Secondly, the data processing means must be made compatible with the evolving and modular characteristics of the installation. Finally, it is desirable that the data processing means should be as easily adaptable to each particular application as are the various modules which make up the installation.
Preferred implementations of the present invention provide a satisfactory solution to the above requirements.